1. Field of the Present Invention
The present invention relates in general to improved client/server data communication systems and, more particularly, to an improved electronic mail system for use within a client/server data communication system. Still more particularly, the present invention relates to a method and system for an electronic mail system to reliably delete messages from a server independent of a protocol utilized by the client/server data communication system for transmitting data where at least one protocol utilized by a client does not provide an explicit delete signal.
2. Description of the Related Art
Computers are well-known in the art and have become a business staple as well as being utilized in many homes. One feature available through computers is that of using electronic mailing (e-mail) to send messages to and receive messages from other computers by a server system. E-mail allows clients of a network system, which is maintained, by a server system, to send messages or data from one user to another. The network system may include a fixed group of computers connected across a local area network (LAN) or may be a medium such as the xe2x80x9cInternetxe2x80x9d which includes millions of computers, each with access to a server which is part of a large server system infrastructure. A client system typically allows the user to perform such operations as composing, updating, and sending e-mail messages while the server in such a system provides a server based message repository, as well as providing message transmission and reception functions for the user at the client level.
Multiple software applications have been developed to support the user in performing the aforementioned e-mail operations. Beneath the software, multiple protocols have also been developed which aid in the transfer of data and messages. One well-known internet messaging protocol is the Post Office Protocol (POP). Users are provided the ability to send and receive messages transferred across the internet through POP. In addition, POP provides for attaching to messages other data such as a graphic or audio block.
Another internet based client/server communication protocol is known as Open Financial Exchange (OFX). OFX is a unified specification for the electronic exchange of financial data between financial institutions, businesses and consumers via the internet. OFX supports both synchronous and asynchronous transfers of data. In an example of synchronous transfer, a client may synchronously connect with a server to obtain an accurate status of all recent and scheduled transactions for a checking account where data is packaged in the OFX protocol. The user may then view the data through a financial based software application that supports OFX protocol. Since the data is transferred through a server to the client synchronously, the data does not need to be stored in the server for later retrieval. In another example, users may engage in asynchronous use by utilizing a mail template within the financial software application to compose and send a message to an account manager requesting a response to a specific question. The message is packaged in OFX protocol when sent to the server, but may be converted into another protocol by the server for transmitting the message across the internet to another server from which the account manager may receive the message. The account manager may provide a message in response at any time after receiving the message. After the message has been received at the client""s designated server, the user could then request the response from the server at any time. The server would convert the response message back into OFX protocol before sending the response message to the client.
As users of a client/server system expand, the number of protocols utilized within a single client are also expanding. For example, a single client may include one piece of software supported by POP and another piece of software supported by OFX. A server must understand and process data in both types of protocol. However, not all protocols include the same functions needed by the server to correctly process data packaged in different protocols. For example, POP includes a reply to the server of an explicit delete signal if the message has been received and viewed at a client system such that the server can delete the message from storage with a high degree of security that the message has been properly delivered. However, OFX does not include an explicit delete signal to the server after a transmittal since the protocol is typically utilized for synchronous transfer of data. Since servers are typically programmed such that a receipt of delivery is required before a message may be deleted from the server, the lack of receipt from OFX may cause the server to utilize resources unnecessarily in order to store messages which have been properly delivered in OFX protocol. In another method, for the server to reduce the resources utilized by undeleted messages in OFX protocol, the server may retain all data until a receipt of delivery is received or until the resources for saving data are exhausted whereby the last data in the queue would be deleted. However, by this method, data may be deleted before it has been delivered.
From the foregoing, it should be apparent to one skilled in the art that a need exists for a method of reliably deleting messages from a server which may support multiple protocols where at least one of the protocols supported does not provide an explicit delete signal.
It is therefore one object of the present invention to provide an improved client/server data communication system.
It is another object of the present invention to provide an improved electronic mail system for use within a client/server data communication system.
It is yet another object of the present invention to provide a method and system for an electronic mail system to reliably delete messages independent of a protocol utilized by the client/server data communication system for transmitting data where at least one protocol utilized by a client does not provide an explicit delete signal.
The foregoing objects are achieved as is now described. A method and system are disclosed for reliably deleting messages from an electronic mail server system, where the electronic mail server system operates within a client/server network system having at least one client connected to a server and operates independently of a protocol utilized by the client/server network system between the client and the server, where at least one protocol utilized by the client does not provide an explicit delete signal. The client requests a transmission of messages from the server. A list of references to the requested messages to be transmitted from the server is logged within the server. The requested messages are then transmitted from the server to the client. The client may send an acknowledgement of the reception of the transmission of the requested messages from the server to the client in a first protocol layer. However, if the acknowledgement is not sent in the first protocol layer, then the reception of the requested messages is inferred. A reception is inferred if an acknowledgement is searched for and found in a second protocol layer which is associated with the transmission of the requested messages. The list of the requested messages is retrieved upon acknowledgement of reception of the requested messages which are referenced in the list of the requested messages. The messages referenced in the retrieved list of the requested messages are automatically deleted from the server such that requested messages transmitted in a protocol which does not provide an explicit delete acknowledgement may be automatically deleted from the server.